Spatial distribution of soil available nutrients and their impact on blueberry quality in Chengjiang blueberry production area

【Objective】 The purpose of the study was to analyze the current status of soil available nutrients and fruit quality in the open-air blueberry production area of Chengjiang， Yunnan and to explore the impact of soil available nutrients on blueberry quality.【Method】 In Chengjiang blueberry production area，180 soil samples and 18 blueberry fruit samples were collected. The spatial distribution of soil available nutrients in Chengjiang blueberry production area was analyzed， and the fruit quality of three blueberry varieties（Spring height，Jewelry，Emerald）was comprehensively evaluated by principal component analysis. Pearson analysis and linear regression analysis were used to explore the correlation between soil available nutrients and blueberry fruit quality.【Result】 The soil pH in Chengjiang blueberry production area was at a suitable level，the contents of organic matter and alkali-hydro nitrogen were at a low level，and the contents of available phosphorus and available potassium were at a high level. The soil pH in the production area was relatively stable，but soil organic matter， alkali-hydro nitrogen available phosphorus and available potassium all belonged to strong variability levels，among which the available potassium had the highest coefficient of variation（97.04%），indicating that the soil nutrient content in the production area had strong spatial heterogeneity. The correlation among nutrient indexes in blueberry planting soil was closer than that in non-blueberry planting soil. The comprehensive quality of three kinds of blueberry fruits was ranked as Emerald＞Jewelry＞Spring height. The quality of blueberry fruit was significantly correlated with soil pH， alkali-hydro nitrogen，available phosphorus and available potassium（P＜0.05），with the content of avai-lable potassium in soil being the most closely related to the quality of blueberry fruit. The optimal ranges of soil pH，alkali-hydro nitrogen， available phosphorus and available potassium for improving blueberry quality were 4.5-4.9，60.00-90.00 mg/kg，25.00- 50.00 mg/kg and 400.00-500.00 mg/kg respectively.【Conclusion】In order to improve the quality of blueberry fruits， Chengjiang blueberry planting area can adjust the planting structure of different blueberry varieties according to the comprehensive quality ranking of the fruits，and carry out unified and standardized management. At the same time，growers can appropriately increase the soil organic matter and alkali-hydro nitrogen content，and control the amount of potassium and phosphorus fertilizer used.